Solar cells for shingled solar cell module, shingled solar cell module, and method of making solar cells

ABSTRACT

The present disclosure relates to solar cells for a shingled solar cell module, a shingled solar cell module, and a method of making solar cells for the shingled solar cell module. Said solar cell has a front side and a back side, a plurality of front side busbars being arranged on the front side, a plurality of back side busbars being arranged on the back side, the solar cell comprising a plurality of sections, each section comprising a front side busbar and a back side busbar located at edges thereof, the front side busbar of at least one section of the solar cell having an extension at one end or both ends, the extension extending along another edge of said at least one section intersecting with the above-mentioned edges. The shingled solar cell module is fabricated from solar cell strips split from the solar cell.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.16/553,118, filed Aug. 27, 2019, which is a continuation ofInternational Application No. PCT/CN2018/119519, filed on Dec. 6, 2018,which claims priority from Chinese Application No. 201811385343.9 filedon Nov. 20, 2018. All of the abovementioned applications are herebyincorporated by reference in their entirety.

FIELD

The present disclosure relates to solar cells for a shingled solar cellmodule, a shingled solar cell module, and a method of making the solarcells for the shingled solar cell module.

BACKGROUND

As conventional fossil energy such as coal, petroleum and natural gas isconsumed at a faster speed worldwide, ecological environment isdeteriorating, especially the greenhouse gas emissions leads toincreasingly severe global climate change, and the sustainabledevelopment of human society has been seriously threatened. Countriesaround the world have developed their own energy development strategiesto cope with the limitations of conventional fossil energy resources andthe environmental problems brought about by development and utilization.The solar energy has become one of the most important renewable energysources due to its characteristics such as reliability, safety,extensiveness, longevity, environmental protection and resourceadequacy, and is expected to become a main pillar of the global powersupply in the future.

Under the background of vigorously promoting and using green solarenergy, the shingled solar cell module technology can significantlyimprove the efficiency of the module. The process of fabricating theshingled solar cell module has certain requirements for the solar cellpattern design. The conventional design of the shingled cells uses thecut solar cell strips to fabricate the shingled solar cell module. Dueto the asymmetric solar cell busbar design, the current collecting pathis long. In the electroluminescence (EL) image of the shingled solarcell module, the image brightness at both ends at the cell edges isdarker than in the middle, which affects the final power output of themodule.

In particular, since the conventional monocrystalline silicon wafer forproducing the shingled solar cell module has chamfered corners, theshingled solar cell string does not have a sufficient cell-conductiveadhesive-cell connection at the corresponding positions. The effectivewidth of the busbar of the solar cell strip at the edge of the solarcell is shorter than that of the middle. As such, when the chamferedstrip is used to make the shingled solar cell module, the currentcollecting path of the chamfered part is long and the resistance ishigh, which causes the area to be darker than the middle in the ELimaging, affecting the power output of the module.

SUMMARY

An object of the present disclosure is to provide a solar cell for ashingled solar cell module, which can overcome the deficiencies of theprior art.

Said object is achieved by a solar cell for a shingled solar cell moduleaccording to the disclosure, said solar cell having a front side and aback side, a plurality of front side busbars being arranged on the frontside, a plurality of back side busbars being arranged on the back side,the solar cell comprising a plurality of sections, each sectioncomprising a front side busbar and a back side busbar located at edgesthereof, the front side busbar and/or back side busbar of at least onesection of the solar cell having an extension at one end or both ends,the extension extending along another edge of said at least one sectionintersecting with the edges.

The present disclosure, by extending the front side busbar, increasesthe current collecting capability of the busbar, thereby improving theefficiency of the shingled solar cell module.

In accordance with a preferred embodiment of the present disclosure, thesolar cell has chamfered corners, and an extension of the front sidebusbar and/or back side busbar of at least one chamfered section of thesolar cell having a chamfer extends along another edge of the chamferedsection intersecting with the edges of the section where the front sidebusbar and/or back side busbar locates. For example, when the front sidebusbar and/or back side busbar are along a long edge of a chamfer-freeside of the chamfered section, after the front side busbar and/or backside busbar reach another edge of the chamfered section orthogonal withthe long edge, namely, a short edge of the chamfered section, the frontside busbar and/or back side busbar continues to extend along the shortedge. Herein, the busbar in the chamfered portion is extended so thatthe current collecting capacity of the busbar at the chamfered portionis enhanced, thereby improving the EL imaging of the shingled solar cellmodule and improving the efficiency of the chamfered module.

Preferably, the extension may extend along a partial or entire area ofthe another edge of the chamfered section.

Further preferably, the extension may extend along an entire area of theanother edge of the chamfered section and continue to extend along apartial or entire area of a further edge of the chamfered section thatabuts against the another edge. For example, when the front side busbaris along the long edge of the chamfer-free side of the chamferedsection, after the front side busbar reaches other edge of the chamferedsection perpendicular to the long edge, i.e., a short edge of thechamfered section, the front side busbar continues to extend along theentire area of the short edge and continues to extend along another edgeof the chamfered section that abuts against the short edge, i.e., extendalong a partial or entire area of the chamfered edge.

According to a preferred embodiment of the disclosure, the extension mayextend linearly with a constant width or with a non-constant width.

According to a preferred embodiment of the present disclosure, theplurality of front side busbars are distributed evenly spaced apart onthe front side.

According to a preferred embodiment of the present disclosure, theplurality of front side busbars are distributed unevenly spaced apart onthe front side.

Preferably, the plurality of front side busbars may include two frontside busbars which are adjacent to each other, and the two front sidebusbars are not close to the edges of the solar cell with respect toother front side busbars.

Preferably, the plurality of front side busbars may include two pairs offront side busbars, and two front side busbars of each pair of the twopairs of front side busbars are adjacent to each other, and the twopairs of front side busbars adjacent to each other are respectivelyclose to one edge of the solar cell.

Preferably, the plurality of front side busbars may include two frontside busbars which are adjacent to each other, and the two front sidebusbars are close to the edge of the solar cell.

Preferably, the plurality of front side busbars may include two pairs offront side busbars, and two front side busbars of each pair of the twopairs of front side busbars are adjacent to each other, and one pair ofthe two pairs of front side busbars are close to the edge of the solarcell, and the other pair of the two pairs of front side busbars are notclose to the edge of the solar cell.

According to a preferred embodiment of the present disclosure, thedistribution of the plurality of back side busbars may correspond to thedistribution of the plurality of front side busbars, such that after thesolar cell is split into a plurality of solar cell strips, the frontside busbar is adjacent to a long edge and an adjacent short edge of acorresponding solar cell strip, and the back side busbar is adjacent toan opposite long edge of the corresponding solar cell strip.

According to another aspect of the present disclosure, there is provideda shingled solar cell module which is fabricated from solar cell stripssplit from the solar cell according to any of the above embodiments.

According to a further aspect of the present disclosure, there isprovided a method for fabricating a solar cell for a shingled solar cellmodule. The method comprises: arranging a plurality of back side busbarson a front side and a back side, the plurality of busbars dividing thesolar cell into a plurality of sections, each section comprising a frontside busbar and a back side busbar located at edges thereof, the busbarof at least one section of the solar cell having an extension at one endor both ends thereof, the extension extending along another edge of saidat least one section intersecting with the edges.

According to a preferred embodiment of the present disclosure, in themethod of fabricating a solar cell for a shingled solar cell moduleaccording to the present disclosure, the solar cell has chamfers, and anextension of the busbar of at least one chamfered section of the solarcell having a chamfer extends along another edge of the chamferedsection intersecting with the edge where the busbar locates.

Preferably, in the method of making a solar cell for a shingled solarcell module according to the present disclosure, the extension mayextend along a partial or entire area of the another edge of thechamfered section. Further preferably, the extension may extend along anentire area of the another edge of the chamfered section and continue toextend along a partial or entire area of a further edge of the chamferedsection that abuts against the another edge.

According to a preferred embodiment of the present disclosure, in themethod of making a solar cell for a shingled solar cell module accordingto the present disclosure, the extension may extends linearly with aconstant width or with a non-constant width.

According to a preferred embodiment of the present disclosure, in themethod of making a solar cell for use in a shingled solar cell moduleaccording to the present disclosure, the plurality of busbars may be aplurality of front side busbars. Alternatively, the plurality of busbarsmay be a plurality of back side busbars.

According to a preferred embodiment of the present disclosure, in themethod of making a solar cell for use in a shingled solar cell moduleaccording to the present disclosure, the plurality of front side busbarsare distributed evenly spaced apart on the front side.

According to a preferred embodiment of the present disclosure, in themethod of making a cell for a shingled solar cell module according tothe present disclosure, the plurality of front side busbars aredistributed unevenly spaced apart on the front side.

Preferably, in the method of making a solar cell for a shingled solarcell module according to the present disclosure, the plurality of frontside busbars may include two front side busbars which are adjacent toeach other, and the two front side busbars are not close to the edge ofthe solar cell with respect to other front side busbars.

Preferably, in the method of making a solar cell for use in a shingledsolar cell module according to the present disclosure, the plurality offront side busbars may include two pairs of front side busbars, and twofront side busbars of each pair of the two pairs of front side busbarsare adjacent to each other, and the two pairs of front side busbars arerespectively close to one edge of the solar cell.

Preferably, in the method of making a solar cell for use in a shingledsolar cell module according to the present disclosure, the plurality offront side busbars may include two front side busbars which are adjacentto each other, and the two front side busbars are close to the edge ofthe solar cell.

Preferably, in the method of fabricating a solar cell for use in ashingled solar cell module according to the present disclosure, theplurality of front side busbars may include two pairs of front sidebusbars, and two front side busbars of each pair of the two pairs offront side busbars are adjacent to each other, and one pair of the twopairs of front side busbars are close to the edge of the solar cell, andthe other pair of the two pairs of front side busbars are not close tothe edge of the solar cell.

According to a preferred embodiment of the present disclosure, in themethod of making a solar cell for a shingled solar cell module accordingto the present disclosure, the busbar of at least one section of thesolar cell having an extension at one end or both ends thereof is thefront side busbar.

According to the method of the present disclosure, by the design ofextending the busbar in the chamfered portion, it is possible toincrease the current collecting capability of the busbar at thechamfered portion, thereby improving the EL imaging of the chamferedshingled solar cell module and improving the efficiency of the shingledsolar cell module.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 and FIG. 2 show a front side and a back side of a solar cellaccording to the prior art in a top view and a bottom view,respectively;

FIG. 3 and FIG. 4 show a front side and a back side of a solar cellaccording to a preferred embodiment of the present disclosure in a topview and a bottom view, respectively;

FIG. 5 shows a partial enlarged view showing a chamfered area of thesolar cell of FIG. 3 and FIG. 4;

FIG. 6 and FIG. 7 show a front side and a back side of a solar cellaccording to another preferred embodiment of the present disclosure in atop view and a bottom view, respectively;

FIG. 8 shows a partial enlarged view showing a chamfered area of thesolar cell of FIG. 6 and FIG. 7;

FIG. 9 and FIG. 10 show a front side and a back side of a solar cellaccording to a further preferred embodiment of the present disclosure ina top view and a bottom view, respectively;

FIG. 11 and FIG. 12 show a front side and a back side of a solar cellaccording to a further preferred embodiment of the present disclosure ina top view and a bottom view, respectively;

FIG. 13 and FIG. 14 show a front side and a back side of a solar cellaccording to a further preferred embodiment of the present disclosure ina top view and a bottom view, respectively;

FIG. 15 and FIG. 16 show a front side and a back side of a solar cellaccording to a further preferred embodiment of the present disclosure ina top view and a bottom view, respectively;

FIG. 17 and FIG. 18 show a front side and a back side of a solar cellaccording to a further preferred embodiment of the present disclosure ina top view and a bottom view, respectively;

FIG. 19 and FIG. 20 show a front side and a back side of a solar cellaccording to a further preferred embodiment of the present disclosure ina top view and a bottom view, respectively;

FIG. 21 shows a flow chart of a method for making a solar cell of ashingled solar cell module in accordance with the present disclosure.

DETAILED DESCRIPTION OF EMBODIMENTS

The content of the present disclosure will be described below withreference to the figures. It may be appreciated by those skilled in theart that the present disclosure is not limited thereto, and equivalentcontent also fall within the scope of the present disclosure.

FIG. 1 and FIG. 2 show a front side and a back side of a solar cellaccording to the prior art in a top view and a bottom view,respectively. The solar cell 100 has chamfers 131, 132, 133, 134.

A plurality of front side busbars 101, 102, 103, 104, 105 are arrangedon a front side of the solar cell, and a plurality of back side busbars106, 107, 108, 109, 110 are arranged on a back side of the solar cell.The distribution of the plurality of back side busbars 106, 107, 108,109, 110 corresponds to the distribution of the plurality of front sidebusbars 101, 102, 103, 104, 105 in such a manner that after the solarcell 100 is split into solar cell strips, each solar cell strip has afront side busbar on one side and a back side busbar on the oppositeside.

As shown in FIG. 1 and FIG. 2, the solar cell 100 may be split into fivesolar cell strips. According to the sequence shown in FIGS. 1 and 2,from left to right, the first solar cell strip has a front side busbar101 and a back side busbar 106, the second solar cell strip has a frontside busbar 102 and a back side busbar 107, the third cell strip has afront side busbar 103 and a back side busbar 108, the fourth solar cellstrip has a front side busbar 104 and a back side busbar 109, and thefifth solar cell strip has a front side busbar 105 and a back sidebusbar 110. In particular, the effective width of the busbar of thechamfered solar cell strip at the edge of the solar cell is shorter thanat the middle, so when it is used to make the shingled solar cellmodule, the current collecting path of the chamfered part is longer andthe resistance is higher, which causes the area to be darker than themiddle in the EL imaging, affecting the power output of the module.

The present disclosure improves the prior art design of FIG. 1 and FIG.2, and improves the EL imaging of the shingled solar cell module andimproves the power of the shingled solar cell module by increasing thecurrent collecting capability of the busbar, particularly the currentcollecting capability at the chamfered portion. FIG. 3 through FIG. 12illustrate various preferred embodiments of a solar cell in accordancewith the present disclosure.

FIG. 3 and FIG. 4 show a front side and a back side of a solar cellaccording to a preferred embodiment of the present disclosure in a topview and a bottom view, respectively. The illustrated solar cell 200 isformed by slicing a square rod chamfered at four edges, so that thesolar cell has a substantially square shape with four corners chamferedas viewed from the front side and the back side. That is, the solar cell200 has chamfers 221, 222, 223, and 224.

A plurality of mutually parallel front side busbars 201, 202, 203, 204,205 parallel to two of the edges of the solar cell are disposed on thefront side, and a plurality of mutually parallel back side busbars 206,207, 208, 209, 210 parallel to the same two edges of the solar cell aredisposed on the back side. The solar cell includes a plurality ofjuxtaposed sections 231, 232, 233, 234, 235, and each section includesone front side busbar and one back side busbar.

In this embodiment, the plurality of front side busbars 201, 202, 203,204, 205 are distributed unevenly spaced apart on the front side. Theplurality of front side busbars 201, 202, 203, 204, 205 include twofront side busbars 202, 203 which are adjacent to each other, and thetwo front side busbars 202, 203 are not close to the edge of the solarcell with respect to other front side busbars. In the presentembodiment, two front side busbars 202, 203 are located on the sectionclose to the center of the solar cell. However, the present disclosureis not limited thereto. In other embodiments, the plurality of frontside busbars may be distributed evenly spaced apart on the front side,and the front side busbar may be close to the edge of the solar cell.

The distribution of the plurality of back side busbars 206, 207, 208,209, 210 corresponds to the distribution of the plurality of front sidebusbars 201, 202, 203, 204, 205 in such a manner that after the solarcell 200 is split into the solar cell strips with the above-mentionedsections, each of the solar cell strips has a front side busbar on along edge and a back side busbar on an opposite long edge, and at leastone solar cell strip has a front side busbar on the long edge and ashort edge intersecting therewith. As shown in FIG. 3 and FIG. 4, thesolar cell 200 may be split into five solar cell strips. According tothe sequence shown in FIGS. 3 and 4, from left to right, the first solarcell strip has a front side busbar 201 and a back side busbar 206, thesecond solar cell strip has a front side busbar 202 and a back sidebusbar 207, the third solar cell strip has a front side busbar 203 and aback side busbar 208, the fourth solar cell strip has a front sidebusbar 204 and a back side busbar 209, and the fifth solar cell striphas a front side busbar 205 and a back side busbar 210. As describedabove, each of the first to fifth solar cell strips has a front sidebusbar on a long edge and a back side busbar on an opposite long edge,and at least one solar cell strip in the first to fifth solar cellstrips has a front side busbar at the long edge on one side and a shortedge intersecting therewith, that is, has a busbar at the long edge andhas an extension of the busbar at a short edge intersecting therewith.

Specifically, the two outermost solar cell strips of the first to fifthsolar cell strips, that is, the first solar cell strip and the fifthsolar cell strip have chamfers. The first solar cell strip is also theleft side chamfered section 231, and the fifth solar cell strip is alsothe right side chamfered section 235. The front side busbar 201 of theleft side chamfered section 231 having a chamfer extends along the longedge on the side without chamfer, and after reaching the short edgeintersecting (orthogonal in the present embodiment in the figure) thelong edge, the front side busbar 201 continues to extend along the shortedge, i.e., has an extension 211 of the busbar. FIG. 5 shows a partialenlarged view showing a chamfered 221 area of the solar cell. Theextension 211 of the busbar 201 can be more clearly seen in FIG. 5. Asshown, the extension 211 extends along the short edge 231-1 of thechamfered section 231. The extension 211 may extend all the way to thechamfer 221 or may extend only along a partial area of the short edge231-1 without extending to the chamfer 221. The extension 211 may belinearly and not gradually varied, that is, have a constant width, ormay be linearly and gradually varied, that is, have a variable width.

By designing the extension of the front side busbar at the intersectingshort edge or near the chamfer of the solar cell, it is possible toenhance the current collecting capability of the solar cell and increasethe power of the shingled solar cell module.

Similarly, the front side busbar 205 of the fifth solar cell strip,namely, of the right side chamfered section 235 extends along the longedge of the side without a chamfer, and after reaching the short edgeintersecting (orthogonal in the present embodiment in the figure) withthe long edge, the front side busbar 205 continues to extend along theshort edge, i.e., has an extension of the busbar, the extension extendsalong the short edge of the right side chamfered section 235, theextension may extend all the way to the chamfer 222, or may extend onlyalong a partial area of the short edge without extending to the chamfer222.

Certainly, in the embodiment shown in the figures, the extension of thebusbar is located on the lower short edge that intersects the long edgeof the solar cell strip. As will be understood by those skilled in theart, the extension of the busbar may be disposed at the short edge oneither side or at both the upper short edge and lower short edge whichintersect with the long edge.

FIG. 6 and FIG. 7 show a front side and a back side of a solar cell 300according to another preferred embodiment of the present disclosure in atop view and a bottom view, respectively. The illustrated solar cell 300is formed by slicing a square rod chamfered at four edges, so that thesolar cell has a substantially square shape with four corners chamferedas viewed from the front side and the back side. That is, the solar cell300 has chamfers 321, 322, 323, and 324.

A plurality of mutually parallel front side busbars 301, 302, 303, 304,305 parallel to two of the edges of the solar cell are disposed on thefront side, and a plurality of mutually parallel back side busbars 306,307, 308, 309, 310 parallel to the same two edges of the solar cell aredisposed on the back side. The solar cell includes a plurality ofjuxtaposed sections 331, 332, 333, 334, 335, and each section includesone front side busbar and one back side busbar.

In the embodiment shown in FIG. 6 and FIG. 7, the arrangement of theplurality of front side busbars and the plurality of back side busbarsis the same as that of the embodiment shown in FIG. 3 and FIG. 4, anddetails are not described herein again.

The front side busbar 301 of the chamfered left section 331 extendsalong the long edge on the side without chamfer, and after reaching theshort edge intersecting the long edge, the front side busbar 301continues to extend along the short edge, i.e., has an extension 311 ofthe busbar. FIG. 8 shows a partial enlarged view showing a chamfered 321area of the solar cell. The extension 311 of the busbar 301 can be moreclearly seen in FIG. 8. In the present embodiment, the extension 311extends along an entire area of the short edge 331-1 of the chamferedsection 331 and continues to extend along the chamfered edge 331-2 ofthe chamfered section 331. The extension 311 may extend along the entirearea of the chamfered edge 331-2 or may extend only along a partial areaof the chamfered edge 331-2. The extension 311 may be linearly and notgradually varied, that is, have a constant width, or may be linearly andgradually varied, that is, have a variable width.

On the other side of the solar cell, the busbar 305 of another chamferedsection 335 may also have an extension that may extend along the shortedge of the another chamfered section 335. The extension extends all theway to the chamfer 322, or may extend only along a partial area of theshort edge of the another chamfered section 335 without extending to thechamfer 322. Further preferably, the extension of the busbar 305 mayextend along the entire short edge of the another chamfered section 335and continue to extend along a partial or entire area of the chamferededge of the another chamfered section 335.

Certainly, in the embodiment shown in the figure, the extension of thebusbar is located on the lower short edge that intersects the long edgeof the solar cell strip. As will be understood by those skilled in theart, the extension of the busbar may be disposed at the short edge oneither side or at both the upper short edge and lower short edge whichintersect with the long edge.

FIG. 9 and FIG. 10 show a front side and a back side of a solar cell 400according to a preferred embodiment of the present disclosure in a topview and a bottom view, respectively. The illustrated solar cell 400 isformed by slicing a square rod chamfered at four edges, so that thesolar cell has a substantially square shape with four corners chamferedas viewed from the front side and the back side. That is, the solar cell400 has chamfers 421, 422, 423, and 424.

A plurality of mutually parallel front side busbars 401, 402, 403, 404,405 parallel to two of the edges of the solar cell are disposed on thefront side, and a plurality of mutually parallel back side busbars 406,407, 408, 409, 410 parallel to the same two edges of the solar cell aredisposed on the back side. The solar cell includes a plurality ofjuxtaposed sections 431, 432, 433, 434, 435, and each section includesone front side busbar and one back side busbar.

In the present embodiment, the plurality of front side busbars 401, 402,403, 404, 405 are distributed unevenly spaced apart on the front side.The plurality of front side busbars 401, 402, 403, 404, 405 include twopairs of front side busbars 401, 402 and 404, 405, two front sidebusbars of the two pairs of front side busbars are adjacent to eachother, and the two pairs of front side busbars 401, 402 and 404, 405 arerespectively close to the edges of the solar cell. However, the presentdisclosure is not limited thereto. In other embodiments, the pluralityof front side busbars may be distributed evenly spaced apart on thefront side, and the front side busbar may not be close to the edge ofthe solar cell.

The distribution of the plurality of back side busbars 406, 407, 408,409, 410 corresponds to the distribution of the plurality of front sidebusbars 401, 402, 403, 404, 405 in such a manner that after the solarcell 400 is split into a plurality of solar cell strips with theabove-mentioned sections, each of the solar cell strips has a front sidebusbar at a long edge and a back side busbar at an opposite long edge.As shown in FIG. 9 and FIG. 10, the solar cell 400 may be split intofive solar cell strips. According to the sequence shown in FIGS. 9 and10, from left to right, the first solar cell strip has a front sidebusbar 401 and a back side busbar 406, the second solar cell strip has afront side busbar 402 and a back side busbar 407, the third solar cellstrip has a front side busbar 403 and a back side busbar 408, and thefourth solar cell strip has a front side busbar 404 and a back sidebusbar 409, the fifth solar cell strip has a front side busbar 405 and aback side busbar 410. As described above, each of the first to fifthsolar cell strips has a front side busbar at a long edge and a back sidebusbar at an opposite long edge, and at least one solar cell strip inthe first to fifth solar cell strips has a front side busbar at the longedge on one side and a short edge intersecting therewith, that is, has abusbar at the long edge and has an extension of the busbar at a shortedge intersecting therewith.

Specifically, the two outermost solar cell strips of the first to fifthsolar cell strips, that is, the first solar cell strip and the fifthsolar cell strip have chamfers. The first solar cell strip is also theleft side chamfered section 431, and the fifth solar cell strip is alsothe right side chamfered section 435. The front side busbar 401 of theleft side chamfered section 431 along the long edge on the side withoutchamfer, and after reaching the short edge intersecting (orthogonal inthe present embodiment in the figure) the long edge, the front sidebusbar 401 continues to extend along the short edge, i.e., has anextension 411 of the busbar. The extension 411 extends towards thechamfer 421 along the intersecting short edge 431-1 of the chamferedsection 431. The extension 411 may extend all the way to the chamfer 421or may extend only along a partial area of the intersecting short edge431-1 of the chamfered section 431. The extension 411 may be linearlyand not gradually varied, that is, have a constant width, or may belinearly and gradually varied, that is, have a variable width.

By designing the extension of the front side busbar at the end edge ornear the chamfer of the solar cell, it is possible to enhance thecurrent collecting capability of the solar cell and increase the powerof the shingled solar cell module.

Similarly, the front side busbar 405 of the fifth solar cell strip,namely, of the right side chamfered section 435 extends along the longedge of the side without a chamfer, and after reaching the short edgeintersecting with the long edge, the front side busbar 405 continues toextend along the short edge, i.e., has an extension of the busbar, theextension extends along the short edge of the right side chamferedsection 435, the extension may extend all the way to the chamfer 422, ormay extend only along a partial area of the short edge of anotherchamfered section 435 without extending to the chamfer 422.

Certainly, in the embodiment shown in the figures, the extension of thebusbar is located on the lower short edge that intersects the long edgeof the solar cell strip. As will be understood by those skilled in theart, the extension of the busbar may be disposed at the short edge oneither side or at both the upper short edge and lower short edge whichintersect with the long edge.

FIG. 11 and FIG. 12 show a front side and a back side of a solar cell500 according to a preferred embodiment of the present disclosure in atop view and a bottom view, respectively. The illustrated solar cell 500is formed by slicing a square rod chamfered at four edges, so that thesolar cell has a substantially square shape with four corners chamferedas viewed from the front side and the back side. That is, the solar cell500 has chamfers 521, 522, 523, and 524.

A plurality of mutually parallel front side busbars 501, 502, 503, 504,505 parallel to two of the edges of the solar cell are disposed on thefront side, and a plurality of mutually parallel back side busbars 506,507, 508, 509, 510 parallel to the same two edges of the solar cell aredisposed on the back side. The arrangement of the plurality of frontside busbars and the plurality of back side busbars is the same as thatof the embodiment shown in FIG. 7 and FIG. 8, and details are notdescribed herein again.

The front side busbar 501 of the left side chamfered section 531 extendsalong the long edge on the side without chamfer, and after reaching theshort edge intersecting the long edge, the front side busbar 501continues to extend along the short edge, i.e., has an extension 511 ofthe busbar. The extension 511 extends along an entire area of the shortedge 531-1 of the chamfered section 531 and continues to extend alongthe chamfered edge 531-2 of the chamfered section 531. The extension 511may extend along the entire area of the chamfered edge 531-2 or mayextend only along a partial area of the chamfered edge 531-2. Theextension 511 may be linearly and not gradually varied, that is, have aconstant width, or may be linearly and gradually varied, that is, have avariable width.

Similarly, the front side busbar 505 of the fifth solar cell strip,namely, of the right side chamfered section 523 extends along the longedge of the side without a chamfer, and after reaching the short edgeintersecting with the long edge, the front side busbar 505 continues toextend along the short edge, i.e., has an extension of the busbar, theextension extends along the short edge of another chamfered section 523,the extension may extend all the way to the chamfer 522, or may extendonly along a partial area of the short edge of another chamfered section523 without extending to the chamfer 522. Further preferably, theextension of the busbar 505 may extend along the entire short edge ofthe another chamfered section 523 and continue to extend along a partialor entire area of the chamfered edge of the another chamfered section523.

Certainly, in the embodiment shown in the figures, the extension of thebusbar is located on the lower short edge that intersects the long edgeof the solar cell strip. As will be understood by those skilled in theart, the extension of the busbar may be disposed at the short edge oneither side or at both the upper short edge and lower short edge whichintersect with the long edge.

FIG. 13 and FIG. 14 show a front side and a back side of a solar cell600 according to a preferred embodiment of the present disclosure in atop view and a bottom view, respectively. The illustrated solar cell 600is formed by slicing a square rod chamfered at four edges, so that thesolar cell has a substantially square shape with four corners chamferedas viewed from the front side and the back side. That is, the solar cell600 has chamfers 621, 622, 623, and 624.

A plurality of mutually parallel front side busbars 601, 602, 603, 604,605 parallel to two of the edges of the solar cell are disposed on thefront side, and a plurality of mutually parallel back side busbars 606,607, 608, 609, 610 parallel to the same two edges of the solar cell aredisposed on the back side. The solar cell includes a plurality ofjuxtaposed sections 631, 632, 633, 634, 635, and each section includesone front side busbar and one back side busbar.

In the embodiment, the plurality of front side busbars 601, 602, 603,604, 605 are distributed unevenly spaced apart on the front side. Theplurality of front side busbars 601, 602, 603, 604, 605 include twofront side busbars 604, 605 which are adjacent to each other, and thetwo front side busbars 604, 605 are close to the edge of the solar cellwith respect to other front side busbars. In the present embodiment, twofront side busbars 604, 605 are located on the section at the outermostedge.

The distribution of the plurality of back side busbars 606, 607, 608,609, 610 corresponds to the distribution of the plurality of front sidebusbars 601, 602, 603, 604, 605 in such a manner that after the solarcell 600 is split into the solar cell strips with the above-mentionedsections, each of the solar cell strips has a front side busbar at along edge and a back side busbar on an opposite long edge, and at leastone solar cell strip has a front side busbar at the long edge on oneside and a short edge intersecting therewith. As shown in FIG. 13 andFIG. 14, the solar cell 600 may be split into five solar cell strips.According to the sequence shown in FIGS. 13 and 14, from left to right,the first solar cell strip has a front side busbar 601 and a back sidebusbar 606, the second solar cell strip has a front side busbar 602 anda back side busbar 607, the third solar cell strip has a front sidebusbar 603 and a back side busbar 608, and the fourth solar cell striphas a front side busbar 604 and a back side busbar 609, and the fifthsolar cell strip has a front side busbar 605 and a back side busbar 610.As described above, each of the first to fifth solar cell strips has afront side busbar at a long edge and a back side busbar at an oppositelong edge, and at least one solar cell strip in the first to fifth solarcell strips has a front side busbar at the long edge on one side and ashort edge intersecting therewith, that is, has a busbar at the longedge and has an extension of the busbar at a short edge intersectingtherewith.

Specifically, the two outermost solar cell strips of the first to fifthsolar cell strips, that is, the first solar cell strip and the fifthsolar cell strip have chamfers. The first solar cell strip is also theleft side chamfered section 631, and the fifth solar cell strip is alsothe right side chamfered section 635. The front side busbar 601 of theleft side chamfered section 631 extends along the long edge on the sidewithout chamfer, and after reaching the short edge intersecting(orthogonal in the present embodiment in the figure) the long edge, thefront side busbar 601 continues to extend along the short edge, i.e.,has an extension 611 of the busbar. As shown, the extension 611 extendsalong the short edge 631-1 of the chamfered section 631. The extension611 may extend all the way to the chamfer 621 or may extend only along apartial area of the short edge 631-1 without extending to the chamfer621. The extension 611 may be linearly and not gradually varied, thatis, have a constant width, or may be linearly and gradually varied, thatis, have a variable width.

By designing the extension of the front side busbar at the intersectingshort edge or near the chamfer of the solar cell, it is possible toenhance the current collecting capability of the solar cell and increasethe efficiency of the shingled solar cell module.

Similarly, the front side busbar 605 of the fifth solar cell strip,namely, of the right side chamfered section 635 extends along the longedge of the side without a chamfer, and after reaching the short edgeintersecting (orthogonal in the present embodiment in the figure) withthe long edge, the front side busbar 605 continues to extend along theshort edge, i.e., has an extension of the busbar, the extension extendsalong the short edge of the right side chamfered section 635, theextension may extend all the way to the chamfer 622, or may extend onlyalong a partial area of the short edge without extending to the chamfer622.

Certainly, in the embodiment shown in the figures, the extension of thebusbar is located on the lower short edge that intersects the long edgeof the solar cell strip. As will be understood by those skilled in theart, the extension of the busbar may be disposed at the short edge oneither side or at both the upper short edge and lower short edge whichintersect with the long edge.

FIG. 15 and FIG. 16 show a front side and a back side of a solar cell700 according to another preferred embodiment of the present disclosurein a top view and a bottom view, respectively. The illustrated solarcell 700 is formed by slicing a square rod chamfered at four edges, sothat the solar cell has a substantially square shape with four cornerschamfered as viewed from the front side and the back side. That is, thesolar cell 700 has chamfers 721, 722, 723, and 724.

A plurality of mutually parallel front side busbars 701, 702, 703, 704,705 parallel to two of the edges of the solar cell are disposed on thefront side, and a plurality of mutually parallel back side busbars 706,707, 708, 709, 710 parallel to the same two edges of the solar cell aredisposed on the back side. The solar cell includes a plurality ofjuxtaposed sections 731, 732, 733, 734, 735, and each section includesone front side busbar and one back side busbar.

In the embodiment shown in FIG. 15 and FIG. 16, the arrangement of theplurality of front side busbars and the plurality of back side busbarsis the same as that of the embodiment shown in FIG. 13 and FIG. 14, anddetails are not described herein again.

The front side busbar 701 of the left side chamfered section 731 extendsalong the long edge on the side without chamfer, and after reaching theshort edge intersecting (orthogonal in the embodiment in the figure) thelong edge, the front side busbar 701 continues to extend along the shortedge, i.e., has an extension 711. In the present embodiment, theextension 711 extends along an entire area of the short edge 731-1 ofthe chamfered section 731 and continues to extend along the chamferededge 731-2 of the chamfered section 731. The extension 711 may extendalong the entire area of the chamfered edge 731-2 or may extend onlyalong a partial area of the chamfered edge 731-2. The extension 711 maybe linearly and not gradually varied, that is, have a constant width, ormay be linearly and gradually varied, that is, have a variable width.

On the other side of the solar cell, the busbar 705 of another chamferedsection 735 may also have an extension that may extend along the shortedge of the another chamfered section 735. The extension extends all theway to the chamfer 722, or may extend only along a partial area of theright-angle short edge of the another chamfered section 735 withoutextending to the chamfer 722. Further preferably, the extension of thebusbar 705 may extend along the entire short edge of the anotherchamfered section 735 and continue to extend along a partial or entirearea of the chamfered edge of the another chamfered section 735.

FIG. 17 and FIG. 18 show a front side and a back side of a solar cell800 according to a preferred embodiment of the present disclosure in atop view and a bottom view, respectively. The illustrated solar cell 800is formed by slicing a square rod chamfered at four edges, so that thesolar cell has a substantially square shape with four corners chamferedas viewed from the front side and the back side. That is, the solar cell800 has chamfers 821, 822, 823, and 824.

A plurality of mutually parallel front side busbars 801, 802, 803, 804,805 parallel to two of the edges of the solar cell are disposed on thefront side, and a plurality of mutually parallel back side busbars 806,807, 808, 809, 810 parallel to the same two edges of the solar cell aredisposed on the back side. The solar cell includes a plurality ofjuxtaposed sections 831, 832, 833, 834, 835, and each section includesone front side busbar and one back side busbar.

In the embodiment, the plurality of front side busbars 801, 802, 803,804, 805 are distributed unevenly spaced apart on the front side. Theplurality of front side busbars 801, 802, 803, 804, 805 include twopairs of front side busbars 802, 803 and 804, 805, two front sidebusbars of the two pairs of front side busbars are adjacent to eachother, and a pair of front side busbars 804, 805 in the two pairs offront side busbars are close to an edge of the solar cell, and the otherpair of front side busbars 802, 803 are not close to any edge of thesolar cell.

The distribution of the plurality of back side busbars 806, 807, 808,809, 810 corresponds to the distribution of the plurality of front sidebusbars 801, 802, 803, 804, 805 in such a manner that after the solarcell 400 is split into a plurality of solar cell strips with theabove-mentioned sections, each of the solar cell strips has a front sidebusbar at a long edge on one side and a back side busbar at a long edgeon the other side, and at least one solar cell strip has a front sidebusbar at the long edge on one side and a short edge intersectingtherewith. As shown in FIG. 17 and FIG. 18, the solar cell 800 may besplit into five solar cell strips. According to the sequence shown inFIGS. 17 and 18, from left to right, the first solar cell strip has afront side busbar 801 and a back side busbar 806, the second solar cellstrip has a front side busbar 802 and a back side busbar 807, the thirdsolar cell strip has a front side busbar 803 and a back side busbar 808,and the fourth solar cell strip has a front side busbar 804 and a backside busbar 809, and the fifth solar cell strip has a front side busbar805 and a back side busbar 810. As described above, each of the first tofifth solar cell strips has a front side busbar at a long edge on oneside and a back side busbar at the long edge on the other side, and atleast one solar cell strip in the first to fifth solar cell strips has afront side busbar at the long edge on one side and a short edgeintersecting therewith, that is, has a busbar at the long edge and hasan extension of the busbar at a short edge intersecting with the longedge.

Specifically, the two outermost solar cell strips of the first to fifthsolar cell strips, that is, the first solar cell strip and the fifthsolar cell strip have chamfers. The first solar cell strip is also theleft side chamfered section 831, and the fifth solar cell strip is alsothe right side chamfered section 835. The front side busbar 801 of theleft side chamfered section 831 extends along the long edge on the sidewithout chamfer, and after reaching the short edge intersecting(orthogonal in the present embodiment in the figure) the long edge, thefront side busbar 801 continues to extend along the short edge, i.e.,has an extension 811. The extension 811 extends towards the chamfer 821along the short edge 831-1 of the chamfered section 831. The extension811 may extend all the way to the chamfer 821 or may extend only along apartial area of the short edge 831-1 of the chamfered section 831without extending to the chamfer 821. The extension 811 may be linearlyand not gradually varied, that is, have a constant width, or may belinearly and gradually varied, that is, have a variable width.

By designing the extension of the front side busbar at the intersectingshort edge or near the chamfer of the solar cell, it is possible toenhance the current collecting capability of the solar cell and increasethe efficiency of the shingled solar cell module.

Similarly, the front side busbar 805 of the fifth solar cell strip,namely, of the right side chamfered section 835 extends along the longedge of the side without a chamfer, and after reaching the short edgeintersecting (orthogonal in the embodiment in the figure) with the longedge, the front side busbar 805 continues to extend along the shortedge, i.e., has an extension, the extension extends along the short edgeof the right side chamfered section 835, the extension may extend allthe way to the chamfer 822, or may extend only along a partial area ofthe short edge of another chamfered section 835 without extending to thechamfer 822.

Certainly, in the embodiment shown in the figures, the extension of thebusbar is located on the lower short edge that intersects the long edgeof the solar cell strip. As will be understood by those skilled in theart, the extension of the busbar may be disposed at the short edge oneither side or at both the upper short edge and lower short edge whichintersect with the long edge.

FIG. 19 and FIG. 20 show a front side and a back side of a solar cell900 according to a preferred embodiment of the present disclosure in atop view and a bottom view, respectively. The illustrated solar cell 900is formed by slicing a square bar chamfered at four edges, so that thesolar cell has a substantially square shape with four corners chamferedas viewed from the front side and the back side. That is, the solar cell900 has chamfers 921, 922, 923, and 924.

A plurality of mutually parallel front side busbars 901, 902, 903, 904,905 parallel to two of the edges of the solar cell are disposed on thefront side, and a plurality of mutually parallel back side busbars 906,907, 908, 909, 910 parallel to the same two edges of the solar cell aredisposed on the back side. The arrangement of the plurality of frontside busbars and the plurality of back side busbars is the same as thatof the embodiment shown in FIG. 19 and FIG. 20, and details are notdescribed herein again.

The front side busbar 901 of the left side chamfered section 931 extendsalong the long edge on the side without chamfer, and after reaching theshort edge intersecting the long edge, the front side busbar 901continues to extend along the short edge, i.e., has an extension 911.The extension 911 extends along an entire area of the short edge 931-1of the chamfered section 931 and continues to extend along the chamferededge 931-2 of the chamfered section 931. The extension 911 may extendalong the entire area of the chamfered edge 931-2 or may extend onlyalong a partial area of the chamfered edge 931-2. The extension 911 maybe linearly and not gradually varied, that is, have a constant width, ormay be linearly and gradually varied, that is, have a variable width.

Similarly, the front side busbar 905 of the fifth solar cell strip,namely, of the right side chamfered section 923 extends along the longedge of the side without a chamfer, and after reaching the short edgeintersecting with the long edge, the front side busbar 905 continues toextend along the short edge, i.e., has an extension, the extensionextends along the short edge of another chamfered section 935, theextension may extend all the way to the chamfer 922, or may extend onlyalong a partial area of the short edge of another chamfered section 935without extending to the chamfer 922. Further preferably, the extensionof the busbar 905 may extend along the entire short edge of the anotherchamfered section 923 and continue to extend along a partial or entirearea of the chamfered edge of the another chamfered section 935.

FIG. 21 shows a flow chart of a method of making a solar cell for ashingled solar cell module in accordance with the present disclosure.The method includes the following steps:

a step of arranging back side busbars: arranging a plurality of backside busbars on the back side;

a step of arranging front side busbars: arranging a plurality of frontside busbars on a front side of the solar cell, the plurality of frontside busbars dividing the solar cell into a plurality of sections, thefront side busbars being arranged as shown in FIG. 3 and FIG. 6, orbeing arranged as shown in FIG. 13 and FIG. 15, or being arranged asshown in FIG. 17 and FIG. 19; enabling a front side busbar of at leastone section of the solar cell, for example a chamfered section having achamfer, to have an extension at one end or both ends, the extensionextending along an edge of said at least one section;

the distribution of the plurality of front side busbars corresponds tothe distribution of the plurality of back side busbars, such that afterthe solar cell is split into a plurality of solar cell strips, one sideof each solar cell strip is a front side busbar, and the other side is aback side busbar.

The extension of the front side busbar may extend along a partial orentire area of the short edge of the chamfered section. Furtherpreferably, the extension may extend along the entire area of the shortedge of the chamfered section and continue to extend along a partial orentire area of the chamfered edge of the chamfered section. Theextension may be linearly and not gradually varied, or linearly andgradually varied.

By means of the method according to the disclosure, the solar cell hasan extension of the busbar, in particular at the intersecting short edgeor near the chamfer, which enhances the current collecting capability ofthe solar cell and increases the efficiency of the shingled solar cellmodule.

It may be appreciated by those skilled in the art that the above is onlya specific description of the preferred embodiments of the inventiveconcept. According to the present disclosure, the arrangement of thefront side and/or back side busbars of the solar cell may be uniform ornon-uniform in the solar cell. After the solar cell is divided intosolar cell strips, each of the solar cell strips has a front side busbarat a long edge on one side and a back side busbar at a long edge on theother side, and at least one solar cell strip in the solar cell stripshas a busbar (front side busbar and/or back side busbar) at the longedge on one side and a short edge intersecting therewith, that is tosay, has a busbar at the long edge and has an extension of the busbar ata short edge intersecting with the long edge.

The scope of the disclosure is defined only by the claims. Due to theteaching of the present disclosure, those skilled in the art willreadily appreciate that alternative structures of the structuresdisclosed in the present disclosure may be considered as possiblealternative embodiments, and the embodiments disclosed in the presentdisclosure may be combined to produce new embodiments, or the disclosuremay be applied to other similar fields, and they also fall within thescope of the appended claims.

What is claimed is:
 1. A solar cell for a shingled solar cell module, said solar cell having a front side and a back side, a plurality of front side busbars arranged on the front side, and a plurality of back side busbars arranged on the back side, comprising: a plurality of sections, each section comprising a front side busbar and a back side busbar located at edges thereof, wherein each front side busbar has a main body that extends along an edge of its respective section that is not an edge of the solar cell, wherein the solar cell has chamfers, and the front side busbar of at least one chamfered section of the solar cell has an extension at an end of its main body, the extension extending along an entire length of another edge of the chamfered section intersecting with the edge where the main body of the front side busbar of the section is located, and continues to extend along a partial or entire length of a chamfered edge of the chamfered section that abuts against the another edge, wherein the extension extends linearly with a non-constant width, and wherein the plurality of front side busbars include two front side busbars which are adjacent to each other, and the two front side busbars are more close to an outer edge of the solar cell that runs parallel to the main bodies of the front side busbars than all of the other front side busbars of the solar cell.
 2. The solar cell according to claim 1, wherein the solar cell is configured to split into a plurality of solar cell strips, the distribution of the plurality of back side busbars corresponds to the distribution of the plurality of front side busbars, and wherein a front side busbar of a solar cell strip of the plurality of solar cell strips is adjacent to a long edge at one side and an adjacent short edge of the solar cell strip, and a back side busbar of the solar cell strip is adjacent to a long edge at the other side of the solar cell strip.
 3. A shingled solar cell module which is made from solar cell strips split from the solar cell according to claim
 1. 4. A method of making a solar cell for a shingled solar cell module, the method comprising: arranging a plurality of front side busbars on a front side of the solar sell and a plurality of back side busbars on a back side of the solar cell, the plurality of front side busbars and backside busbars dividing the solar cell into a plurality of sections, each section comprising a front side busbar and a back side busbar located at edges thereof, each front side busbar having a main body that extends along an edge of its respective section that is not an edge of the solar cell, wherein the solar cell has chamfers, and the front side busbar of at least one chamfered section of the solar cell has an extension at an end of its main body, the extension extending along an entire length of another edge of the chamfered section intersecting with the edge of the section where the main body of the front side busbar of the section is located, and continues to extend along a partial or entire length of a chamfered edge of the chamfered section that abuts against the another edge, wherein the extension extends linearly with a non-constant width, and wherein the plurality of front side busbars include two front side busbars which are adjacent to each other, and the two front side busbars are more close to an outer edge of the solar cell that runs parallel to the main bodies of the front side busbars than all of the other front side busbars of the solar cell.
 5. The method of claim 4, further comprising splitting the solar cell into a plurality of solar cell strips, wherein the distribution of the plurality of back side busbars corresponds to the distribution of the plurality of front side busbars, and wherein a front side busbar of a solar cell strip of the plurality of solar cell strips is adjacent to a long edge at one side and an adjacent short edge of the solar cell strip, and a back side busbar of the solar cell strip is adjacent to a long edge at the other side of the solar cell strip.
 6. The method of claim 4, further comprising assembling a shingled solar cell module from solar cell strips split from the solar cell.
 7. The solar cell according to claim 1, wherein the width of the extension decreases along the chamfered edge.
 8. The method of claim 4, wherein the width of the extension decreases along the chamfered edge. 